Hi Glen,
I spent a long time looking at your photos last night and was inclined to
suggest that the piston damage was not due to detonation or pre-ignition
rather a straightforward case of overheating. I was also going to suggest it
was number 4 piston that had suffered the damage.
BUT
After looking at a tuning book I have that has some photos of detonation
damaged pistons in it decided to say nothing.
However, now that I know it is definititely no 4 Piston I am not so sure.
You might just want to consider some cooling mods like fitting a blanking
sleeve in place of the thermostat and blocking of the bypass.
You might want to consider some boost-retard ignition system or MG Turbo
metro distributor.
Daniel1312
In a message dated 01/02/01 09:54:49 Pacific Standard Time,
grbyrns@ucdavis.edu writes:
<< I forgot to mention that the pictures of the burned piston are both of the
same piston. On the backside of the #4 piston, you can see the hole burned
at the top and between the 'land' between #1 and #2 compression ring. On
the front side of the same piston shown in the other shot you can see that a
2" piece of the piston has been broken off. It was nestled nicely in place
when the piston came out and fell away in my hand as it came out of the
bore. Just to complete the damage, the wrist pin was badly galled in the
normally slip fit piston holes, and barely moved at all with mucho force.
The huge hole in the head gasket you can see in the photo was between the #3
and #4 cylinder.
Those of you who drove the Frostbite 200 with me and thought my car was
quick... wait until you see it with all four cylinders working!
http://albums.photopoint.com/j/AlbumIndex?u=1416965&a=10597779
(if you like to see post mortem photos)
Regards,
Glen Byrns >>
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